Pump



June 14, 1932. J, HOLVECK PUMP Filed May 17.. 1929 RE M iiilllilPatented Jun '14, 1932 UNITED STATES PATENT OFFICE JOSEPH E. HOLVECK, OFPITTSBURGH, PENNSYLVANIA, ASSIGNOR TO THE ALDRICH PUMP COMPANY, ACORPORATION OF PENNSYLVANIA PUMP Application filed May 17, 1929. SerialNo. 863,891.

This invention relates to pumps and more particularly to a compensatingdevice for eliminating the surge or pressure variationsin the dischargeof pumps such, for example, as hydraulic pumps.

An object of this invention is to provide a device for use withreciprocating pumps constructed and arranged so as to eliminate thesurge or variations in pressure always present in discharge lines ofsuch pumps.

A further object is to provide a compensating device of the type setforth which can be readily applied to pumps already in operation.

A further object is to provide a compensating device of the type setforth which will be simple and rugged in construction efficient inoperation and easy to manufacture and install.

These and other objects which will be apparent to those skilled in thisart, are accomplished by means of the invention illustrated in theaccompanying drawing, in which Figure 1 is a side elevation of areciprocating 5 pump provided with one embodiment of this invention.Figure 2 is a similar view taken from the right of Figure 1. Figure 3 isa partial sectional view through a compensating device constructed inaccordance with one embodiment of this invention.

The particular embodiment of this invention which has been chosen forthe purposes of illustration is shown in connection with a triplexreciprocating pump of standard form. The invention includes a separatecompensator cylinder which is open to the discharge line of the pump. Aplunger is associated with this compensator cylinder and is operated insuch a manner that when the discharge flow of'the pump is above thedesired mean, the plunger will move outwardly so as to permitthecompensator cylinder to absorb the excess water or other material fromthe discharge line of the pump. On the other hand, when the pumpdischarge is less than the mean, the plunger will be moved into thecylinder and force the surplus water back into the discharge line at arate which will bring the discharge flow up to the desired 50 means.

In the illustrated embodiment the compensator plunger is operated bymeans of a cam which is secured directly to the crank shaft of the pump.the layout of the cam being determined from ordinary well known engi,

rod 13 and plunger 11 in the cylinder casing 10, the latter is providedwith packings 16 and 17 respectively, held in position by glands 18 and19, respectively.

The plunger 11 has a yoke 21 rigidly secured at the outer end forsupporting a roller 27 on a small axle 22. This roller 27 is adapted inany suitable manner for rotation in respect to its yoke 21, and forengagement with a suitably designed cam 28.

This cam 28 is adapted to be secured to and v rotatable with the crankshaft 44 of a suit able multi-cylinder pump 30.

The extending rod 13 of the plunger 11 is provided with an encirclingspring 24 whichsis held in place between the gland 18 7 and a washer. 25by a lock nut 26 threaded on the end of this rod 13. This spring is ofsufiicient strength to reduce the thrust of the roller 27 against thecam 28. In other words,

of sufficient strength so that the encircling spring 24 will resist thepressure inthe cylinder chamber 12 just enough to permit sufficientforce on the plunger 11 to keep the roller 27 against the cam 28 and tocushion the piston against pressure of liquid in the cylinder. Thus, thepiston 11 is sensitive to the pressure in the discharge line, therebylessening the operating burden of the cam 28.

The cylinder casing or wall 10, as seen from Figure 3, has an inner andcentralling disposed cylinder or chamber 12 whose diameter 2' rseaeaa islarger than the diameter of the plunger tial plunger 11 will have movedinto the cyl- 11 operative therein. It will be noted that inder 12 andforced out into the discharge the plunger .11, having an upper pistonporline of the pump 30 sufficient liquid to bring tion terminating in alower rod portion, is the discharge thereof up to the mean desired.

' g completely encircled by the wall through In employing this inventionthe port 14 is 70 the opposite ends of which it extends. Furconnectedwith the discharge line 15 of such ther, the opposite ends of the casing10 have a pump as 30, as the cylinder 10 is rigidly seinwardly extendingslots of a diameter somecured at a suitable position on the frame whatgreater than the diameter of the plung and cam 28 is rigidly secured tothe end of m or portion received therein, which near the the crank shaft44: for rotation therewith in outer edges are threaded to receive glands18 timed relation thereto. and 19. These glands 18 and 19 are employedWhat 1 claim as new and desire to secure by to hold suitable packing, 16and 17, respec- L t rs Patent is:

tively, within the enlarged slotted portions. 1- The combination with adischarge appam The upper or piston portion of the plunger ratus havinga crank shaft and a discharge member 11 in normal position i dispo edline, of means secured to said apparatus and somewhat above the centralportion of the cooperating therewith for maintaininga coninner cylinderor cha ber 12, Thi i eeeomstant rate of flow in said discharge line,said plished by positioning a spiral s ring 24 ove means including acylinder casing having a 2a the extending rod portion 13 of the memberchamber in open communication with said @5 11 and holding it in placebetween the lower line, a plunger associated with said chamber gland 18and a nut and wash r m an 25-26 and having a piston portion terminatingat positioned at the extreme end of the rod 13. one end in a rodportion, said portions ex- Thus, it will be seen that, apart from thetending through opposite ends of said casas central chamber 12, thedevice has no air ing, a resilient means positioned on the ex- 9chamber, but completely encircles the plungtending rod portion of saidplunger for holder 11 to prevent any air whatsoever getting ing saldplunger in a normal position, a into the fluid chamber 12 and thusupsetplunger-operating-cam secured to said crank ting the charteddischarge rate. shaft for moving said plunger, so that said 80 Thedevice is adapted for use with any plunger will be operated to forcemore liquid multi-cylinder pump 30 such as shown in into the dischargeline when the discharge of Fig. 2; the particular pump illustrated behappa a us is below mean. ing of a Vertical triplex single acting type;2. The combination with a discharge apbut, it will be apparent that thisinventi n paratus having a crank shaft and a discharge as can b dil d ptd t a y in l o d line, of means secured to said apparatus and ble actingtype of multi-cylinder pump. cooperating therewith for maintaining acon- As shown, the pump 30 is operated bymeans stant rate of flow insaid discharge line, said of any suitable source of power 29 provided mans including a cylinder casing in open with a shaft 31 and a coupling33. This cow communication with said line, a plunger assoli d i th h ft32 d i iti d ciated with said cylinder and having a piston 305 b tw thframe 35 f th pump d an portion terminating at one end in a rodporauiriliary supporting structure 36. A. gear tion, said portionsextending through oppo- 34 is rigidly secured to this shaft 32 for ro-Si ends of said casing, the extending por tation therewith. This gear 3meshes with a tions of said plunger being sealed at entry as gear 35which drives the crank shaft 44 of into Said y d r c ng, S that S d a1110 the pump. The plungers of this pump are her will be air-proof, aresilient means disindicated as 37, 38 and 39 in the drawing and po edon he extending rod portion of said the suction line as 40 and thedischarge line plunger for holding said plunger in a normal as 15.;position, and a plunger-operating-cam se- Efl In practice, the design ofthe circumference Cured to said crank shaft for moving said of the cam28 is in conformity with the curve plunger, so that said plunger will beoperated of the combined discharge of the cylinders o o ce more liquidinto the discharge line of the pump at any given interval and for a whenthe discharge from the apparatus is complete revolution of the crankshaft. below mean.

55 Point 50 of this cam 22 represents a point on 3. The combination witha discharge apthe curve of the discharge of the pump when paratus havinga crank shaft and a discharge it is below meamand 51 a point when theline, of means secured to said apparatus and discharge is above mean.cooperating therewith for maintaining a con- In general, the cam 28 isso timed that when stant rate of flow in said discharge line, said mlthe discharge of the pump is above mean or means including a cylindercasing in open at a point such as 51, the differential plungercommunication with said line, a plunger assowill have moved out in itscompensating cylciated with said cylinder and having a piston inder12,taking the excess discharge fluid into portion terminating at one endin a rod porthe cylinder, but when the discharge is less tion, saidportions extending through oppothan means, such as atapoint 50, thedifierensite ends of said casing, said piston portion 1 having adiameter less than the diameter of said chamber, the extending portionsof said plunger being sealed at entry into said casing so that saidchamber will beair-proof, a resilient means disposed on the extendingrod portion of said plunger for holding said plunger in a normalposition, a plunger-operating-cam secured to said crank shaft for movingsaid plunger, so that said plunger will be operated to force more liquidinto the discharge line when the discharge from the apparatus is belowmean.

4. The combination with a discharge apparatus having a crank shaft and adischarge line, of means secured to said apparatus and cooperatingtherewith for maintaining a constant rate of flow in said dischargeline, said means including a cylinder casing having an inner chamber inopen communication with said line, a plunger associated with saidchamber and having a piston portion terminating at one end in a rodportion, said portions extending through opposite ends of said casing,the extending portions of said plunger being sealed by gland and packingmeans from entry into said casing until entry into said chamber so thatsaid chamber will be air-proof, a re silient means positioned on saidextending rod between the end thereof and the face of the casing, sothat said plunger will maintain a given position with respect to saidchamber, a plunger-operating-cam secured to said crank shaft for movingsaid plunger, said cam having a circumferential out-line conforming tothe curve of the combined discharge of the units of said dischargeapparatus, so that said plunger will be operated to force more liquidinto the discharge line when the discharge from the apparatus is belowmean.

5. The combination with a discharge apparatus having a crank shaft and adischarge line, of means secured to said apparatus and cooperatingtherewith for maintaining a constant rate of flow in said dischargeline, said means including a cylinder casing having an inner chamber inopen communication with said line, a. plunger associated with saidchamber and having a piston portion at one end terminating in a lowerrod portion, said portions extending through opposite ends of saidcasing, said piston portion having a diameter smaller than the diameterof said chamber, the extending portions of said plunger being sealed bygland and packing means from entry into said casing until entry intosaid chamber, so that said chamber will be air-proof, a springpositioned on said cxtending rod between the end thereof and the lowerface of the casing, so that said plunger will maintain a given positionwith respect to said chamber, a plunger-operating-cam secured to saidcrank shaft for moving said plunger, said cam having a circumferentialoutline conforming to the curve of the combined discharge of the unitsof said discharge apparatus, so thatisaid plunger will be operated toforce more liquid into the discharge line when the discharge apparatusis below mean.

6. The combination with a discharge apparatus having a crankshaft and adischarge line, of means detachably secured to said apparatus andcooperating therewith for maintaining a constant rate of flow in saiddischarge line, said means including a cylinder casing having an innerchamber in open communication with said line, a plunger associated withsaid chamber and having an upper piston portion terminating in a lowerrod portion, said portions extending through opposite ends of saidcasing, said piston portion having a diameter less than the diameter ofsaid chamber, the extending portions of said plunger being sealed bygland and packing means from entry into said casing until entry intosaid chamber, so that said chamber will be air-proof, a springpositioned on said extending rod between the end thereof and the lowerface of the casing, so that said plunger will maintain agiven positionwith respcct to said chamber, a plunger-operating cam detachably securedto said crankshaft for moving said plunger, said cam having acircumferential outline conforming to the curve of the combineddischarge of the units of said discharge apparatus, so that said plungerwill be operated to force more liquid into the discharge line when thedischarge from the apparatus is below mean.

7. The combination with a discharge apparatus having a crankshaft and adischarge line, of means detachably secured to said apparatus andcooperating therewith for maintaining a constant rate of flow in saiddischarge line, said means including a cylinder casing having acentrally disposed chamber in open communication with said line, aplunger having an upper piston portion terminating in a lower rodportion, said plunger being disposed for operation in said chamber andbeing positioned to extend through opposite ends of said cylindercasing, the upper of said piston portions having a diameter smaller thanthe diameter of the chamber in which it is disposed for operation, theportions of said plunger extending through the opposite ends of saidcasing being tightly sealed and being positioned to slide therethrough,a resilient means positioned on the extending rod portion of saidplunger and abutting against the lower face of said casing for holdingsaid plunger in a normal position, a plunger-operating cam detachablysecured to said crankshaft for moving said plunger, said cam having acircumferential outline conforming to the curve of the com bineddischarge of the units of said discharge apparatus, so that said plungerwill be 0perated to force more liquid into the discharge line when thedischarge from the apparatus is below mean.

In testimony whereof, I have hereunto sub scribed my name this 11th dayof May, 1929.

JOSEPH E. HOLVECKM

